Re-analysis of the PolyHeme Phase III trial dataset: Lessons for future haemoglobin-based oxygen carrier trauma trials.

INTRODUCTION: To assist design of future HBOC clinical trials for pre-hospital and prolonged field care, the haemoglobin-based-oxygen carrier (HBOC) Phase III trauma trial database comparing PolyHeme to blood transfusion was re-analysed to identify causes of adverse early outcomes versus the 30-day mortality outcome of the original trial. We questioned if failure of PolyHeme (10 g/dl) to increase haemoglobin concentration and dilutional coagulopathy versus blood, caused higher Day 1 mortality in the PolyHeme arm of the trial. METHODS: New analyses of the original trial database, including Fisher's exact test, examined impact of interval changes in total haemoglobin [THb], coagulation, fluid volumes administered and mortality on Day 1 in the Control (pre-hospital crystalloids, then blood after trauma centre admission) and PolyHeme arms of the trial. RESULTS: Admission [THb] was significantly greater (p<0.05) in PolyHeme (12.3 [SD = 1.8] g/dl) versus Control (11.5 [SD= 2.9] g/dl) patients. This early [THb] advantage was reversed within 6 h. Early mortality was negatively correlated with [THb] and maximum 1.4 h after hospital admission (17/365 for Control vs. 5/349 for PolyHeme). The mortality trend began reversing, when Control arm received blood. Coagulopathy was more common in the PolyHeme arm. Mortality rate was 2-fold greater for patients with coagulopathy in the control arm (18% vs. 9%, p = 0.1008) and 4-fold greater in PolyHeme arm (33% vs. 8.5%, p < 0.001). In a subgroup analysis of patients with major haemorrhage (n = 55), mortality was significantly higher in PolyHeme patients [12/26 (46.2%) versus 4/29 (13.8%) in control cohort (p = 0.018)], related to mean 10 liters more IV fluid administration and more severe anaemia (6.2 g/dL vs. 9.2 g/dL) in the PolyHeme cohort. CONCLUSIONS: PolyHeme (10 g/dL) diminished pre-hospital anaemia. The inability of PolyHeme to reverse acute anaemia in a subset of major haemorrhage patients was due to volume overload secondary to high PolyHeme doses, resulting in dilution of clotting factors and low circulating THb (versus transfused controls) during the first 12 h of the trial. Haemodilution was associated with prolonged administration of PolyHeme, while blood transfusion was available to Control patients following hospital admission. Coagulopathy exacerbated bleeding, anaemia, contributing to excess mortality in the PolyHeme arm. Future trials for prolonged field care should evaluate HBOC with higher haemoglobin concentration, lower volume administration and transition upon trauma centre admission to blood plus coagulation factors or whole blood.

Virtual reality and haptic interfaces for civilian and military open trauma surgery training: A systematic review.

OBJECTIVE: Virtual (VR), augmented (AR), mixed reality (MR) and haptic interfaces make additional avenues available for surgeon assessment, guidance and training. We evaluated applications for open trauma and emergency surgery to address the question: Have new computer-supported interface developments occurred that could improve trauma training for civilian and military surgeons performing open, emergency, non-laparoscopic surgery? DESIGN: Systematic literature review. SETTING AND PARTICIPANTS: Faculty, University of Maryland School of Medicine, Baltimore., Maryland; Womack Army Medical Center, Fort Bragg, North Carolina; Temple University, Philadelphia, Pennsylvania; Uniformed Services University of Health Sciences, and Walter Reed National Military Medical Center, Bethesda, Maryland. METHODS: Structured literature searches identified studies using terms for virtual, augmented, mixed reality and haptics, as well as specific procedures in trauma training courses. Reporting bias was assessed. Study quality was evaluated by the Kirkpatrick's Level of evidence and the Machine Learning to Asses Surgical Expertise (MLASE) score. RESULTS: Of 422 papers identified, 14 met inclusion criteria, included 282 enrolled subjects, 20% were surgeons, the remainder students, medics and non-surgeon physicians. Study design was poor and sample sizes were low. No data analyses were beyond descriptive and the highest outcome types were procedural success, subjective self-reports, except three studies used validated metrics. Among the 14 studies, Kirkpatrick's level of evidence was level zero in five studies, level 1 in 8 and level 2 in one. Only one study had MLASE Score greater than 9/20. There was a high risk of bias in 6 studies, uncertain bias in 5 studies and low risk of bias in 3 studies. CONCLUSIONS: There was inadequate evidence that VR,MR,AR or haptic interfaces can facilitate training for open trauma surgery or replace cadavers. Because of limited testing in surgeons, deficient study and technology design, risk of reporting bias, no current well-designed studies of computer-supported technologies have shown benefit for open trauma, emergency surgery nor has their use shown improved patient outcomes. Larger more rigorously designed studies and evaluations by experienced surgeons are required for a greater variety of procedures and skills. COMPETENCIES: Medical Knowledge, Practice Based Learning and Improvement, Patient Care, Systems-Based Practice.

Enhanced Training Benefits of Video Recording Surgery With Automated Hand Motion Analysis.

BACKGROUND: Hand motion analysis by video recording during surgery has potential for evaluation of surgical performance. The aim was to identify how technical skill during open surgery can be measured unobtrusively by video recording during a surgical procedure. We hypothesized that procedural-step timing, hand movements, instrument use and Shannon entropy differ with expertise and training and are concordant with a performance-based validated individual procedure score. METHODS: Surgeon and non-surgeon participants with varying training and levels of expertise were video recorded performing axillary artery exposure and control (AA) on un-preserved cadavers. Color-coded gloves permitted motion-tracking and automated extraction of entropy data from recordings. Timing and instrument-use metrics were obtained through observational video reviews. Shannon entropy measured speed, acceleration and direction by computer-vision algorithms. Findings were compared with individual procedure score for AA performance RESULTS: Experts had lowest entropy values, idle time, active time and shorter time to divide pectoralis minor, using fewer instruments. Residents improved with training, without reaching expert levels, and showed deterioration 12-18 months later. Individual procedure scores mirrored these results. Non-surgeons differed substantially. CONCLUSIONS: Hand motion entropy and timing metrics discriminate levels of surgical skill and training, and these findings are congruent with individual procedure score evaluations. These measures can be collected using consumer-level cameras and analyzed automatically with free software. Hand motion with video timing data may have widespread application to evaluate resident performance and can contribute to the range of evaluation and testing modalities available to educators, training course designers and surgical quality assurance programs.

Comparison of massive and emergency transfusion prediction scoring systems after trauma with a new Bleeding Risk Index score applied in-flight.

BACKGROUND: Assessment of blood consumption (ABC), shock index (SI), and Revised Trauma Score (RTS) are used to estimate the need for blood transfusion and triage. We compared Bleeding Risk Index (BRI) score calculated with trauma patient noninvasive vital signs and hypothesized that prehospital BRI has better performance compared with ABC, RTS, and SI for predicting the need for emergent and massive transfusion (MT). METHODS: We analyzed 2-year in-flight data from adult trauma patients transported directly to a Level I trauma center via helicopter. The BRI scores 0 to 1 were derived from continuous features of photoplethymographic and electrocardiographic waveforms, oximetry values, blood pressure trends. The ABC, RTS, and SI were calculated using admission data. The area under the receiver operating characteristic curve (AUROC) with 95% confidence interval (CI) was calculated for predictions of critical administration threshold (CAT, ≥3 units of blood in the first hour) or MT (≥10 units of blood in the first 24 hours). DeLong's method was used to compare AUROCs for different scoring systems. p < 0.05 was considered statistically significant. RESULTS: Among 1,396 patients, age was 46.5 ± 20.1 years (SD), 67.1% were male. The MT rate was 3.2% and CAT was 7.6%, most (92.8%) were blunt injury. Mortality was 6.6%. Scene arrival to hospital time was 35.3 ± (10.5) minutes. The BRI prediction of MT with AUROC 0.92 (95% CI, 0.89-0.95) was significantly better than ABC, SI, or RTS (AUROCs = 0.80, 0.83, 0.78, respectively; 95% CIs 0.73-0.87, 0.76-0.90, 0.71-0.85, respectively). The BRI prediction of CAT had an AUROC of 0.91 (95% CI, 0.86-0.94), which was significantly better than ABC (AUROC, 077; 95% CI, 0.73-0.82) or RTS (AUROC, 0.79; 95% CI, 0.74-0.83) and better than SI (AUROC, 0.85; 95% CI, 0.80-0.89). The BRI score threshold for optimal prediction of CAT was 0.25 and for MT was 0.28. CONCLUSION: The autonomous continuous noninvasive patient vital signs-based BRI score performs better than ABC, RTS, and SI predictions of MT and CAT. Bleeding Risk Index does not require additional data entry or expert interpretation. LEVEL OF EVIDENCE: Prognostic test, level III.

Prehospital Point of Care Testing for the Early Detection of Shock and Prediction of Lifesaving Interventions.

INTRODUCTION: Early diagnosis and treatment are essential for enhancing outcomes for the traumatically injured. In this prospective prehospital observational study, we hypothesized that a variety of laboratory results measured in the prehospital environment would predict both the presence of early shock and the need for lifesaving interventions (LSIs) for adult patients with traumatic injuries. METHODS: Adult trauma patients flown by a helicopter emergency medical service were prospectively enrolled. Using an i-STAT portable analyzer, data from 16 laboratory tests were collected. Vital signs data were also collected. Outcomes of interest included detection of shock, mortality, and requirement for LSIs. Logistic regression, including a Bayesian analysis, was performed. RESULTS: Among 300 patients screened for enrollment, 261 had complete laboratory data for analysis. The majority of patients were male (75%) with blunt trauma (91.2%). The median injury severity score was 29 (IQR, 25-75) and overall mortality was 4.6%. A total of 170 LSIs were performed. The median lactate for patients who required an LSI was 4.1 (IQR, 3-5.4). The odds of requiring an LSI within the first hour of admission to the trauma center was highly associated with increases in lactate and glucose. A lactate level > 4 mmol/L was statistically associated with greater sensitivity and specificity for predicting the need for a LSI compared with shock index. CONCLUSIONS: In this prospective observational trial, lactate outperformed static vital signs, including shock index, for detecting shock and predicting the need for LSIs. A lactate level > 4 mmol/L was found to be highly associated with the need for LSIs.

Scoping Evidence Review on Training and Skills Assessment for Open Emergency Surgery.

OBJECTIVE: Scope evidence on technical performance metrics for open emergency surgery. Identify surgical performance metrics and procedures used in trauma training courses. DESIGN: Structured literature searches of electronic databases were conducted from January 2010 to December 2019 to identify systematic reviews of tools to measure surgical skills employed in vascular or trauma surgery evaluation and training. SETTING AND PARTICIPANTS: Faculty of Shock Trauma Anesthesiology Research Center, University of Maryland School of Medicine, Uniformed Services University of Health Sciences, Bethesda, Maryland and Implementation Science, King's College, London. RESULTS: The evidence from 21 systematic reviews including over 54,000 subjects enrolled into over 840 eligible studies, identified that the Objective Structured Assessment of Technical Skill was used for elective surgery not for emergency trauma and vascular control surgery procedures. The Individual Procedure Score (IPS), used to evaluate emergency trauma procedures performed before and after training, distinguished performance of residents from experts and practicing surgeons. IPS predicted surgeons who make critical errors and need remediation interventions. No metrics showed Kirkpatrick's Level 4 evidence of technical skills training benefit to emergency surgery outcomes. CONCLUSIONS: Expert benchmarks, errors, complication rates, task completion time, task-specific checklists, global rating scales, Objective Structured Assessment of Technical Skills, and IPS were found to identify surgeons, at all levels of seniority, who are in need of remediation of technical skills for open surgical hemorrhage control. Large-scale, multicenter studies are needed to evaluate any benefit of trauma technical skills training on patient outcomes.

Critical errors in infrequently performed trauma procedures after training.

BACKGROUND: Critical errors increase postoperative morbidity and mortality. A trauma readiness index was used to evaluate critical errors in 4 trauma procedures. In comparison to practicing and expert surgeon benchmarks, we hypothesized that pretraining trauma readiness index including both vascular and nonvascular trauma surgical procedures can identify residents who will make critical errors. METHODS: In a prospective study, trained evaluators used a standardized script to evaluate performance of brachial, axillary, and femoral artery exposure and proximal control and lower-extremity fasciotomy on unpreserved cadavers. Forty residents were evaluated before and immediately after Advanced Surgical Skills for Exposure in Trauma training, and 38 were re-evaluated 14 months later. Residents were compared to 34 practicing surgeons evaluated once 30 months after training, and 10 experts. RESULTS: Resident trauma readiness index increased with training (P < .001), remained unchanged 14 month later and was higher, with lower variance than practicing surgeons (P < .05). Expert trauma readiness index was higher than residents (P < .004) and practicing surgeons (P < .001). Resident training decreased critical errors when evaluated immediately and 14 months after Advanced Surgical Skills for Exposure in Trauma training. Practicing surgeons had more critical errors and performance variability than residents or experts. Experts had 5 to 7 times better error recovery than practicing surgeons or residents. Trauma readiness index area under the receiver operating curve with Youden Index <0.60 or <6 decile in their cohort, predicts a surgeon will make a critical error. CONCLUSION: Low trauma readiness index was associated with critical errors occurring in all surgeon cohorts and can identify surgeons in need of remedial intervention.

Handheld Tissue Oximetry for the Prehospital Detection of Shock and Need for Lifesaving Interventions: Technology in Search of an Indication?

Improved prehospital methods for assessing the need for lifesaving interventions (LSIs) are needed to gain critical lead time in the care of the injured. We hypothesized that threshold values using prehospital handheld tissue oximetry would detect occult shock and predict LSI requirements. This was a prospective observational study of adult trauma patients emergently transported by helicopter. Patients were monitored with a handheld tissue oximeter (InSpectra Spot Check; Hutchinson Technology Inc, Hutchinson, MN), continuous vital signs, and 21 laboratory measurements obtained both in the field with a portable analyzer and at the time of admission. Shock was defined as base excess ≥ 4 or lactate > 3 mmol/L. Eighty-eight patients were enrolled with a median Injury Severity Score of 16 (interquartile range, 5-29). The median hemoglobin saturation in the capillaries, venules, and arterioles (StO2) value for all patients was 82% (interquartile range, 76%-87%; range, 42%-98%). StO2 was abnormal (< 75%) in 18 patients (20%). Eight were hypotensive (9%) and had laboratory-confirmed evidence of occult shock. StO2 correlated poorly with shock threshold laboratory values (r = -0.17; 95% confidence interval, -0.33 to 1.0; P = .94). The area under the receiver operating curve was 0.51 (95% confidence interval, 0.39-0.63) for StO2 < 75% and laboratory-confirmed shock. StO2 was not associated with LSI need on admission when adjusted for multiple covariates, nor was it independently associated with death. Handheld tissue oximetry was not sensitive or specific for identifying patients with prehospital occult shock. These results do not support prehospital StO2 monitoring despite its inclusion in several published guidelines.

Efficacy of Trauma Surgery Technical Skills Training Courses.

OBJECTIVE: Because open surgical skills training for trauma is limited in clinical practice, trauma skills training courses were developed to fill this gap, The aim of this report is to find supporting evidence for efficacy of these courses. The questions addressed are: What courses are available and is there robust evidence of benefit? DESIGN: We performed a systematic review of the training course literature on open trauma surgery procedural skills courses for surgeons using Kirkpatrick's framework for evaluating complex educational interventions. Courses were identified using Pubmed, Google Scholar and other databases. SETTING AND PARTICIPANTS: The review was carried out at the University of Maryland, Baltimore with input from civilian and military trauma surgeons, all of whom have taught and/or developed trauma skills courses. RESULTS: We found 32 course reports that met search criteria, including 21 trauma-skills training courses. Courses were of variable duration, content, cost and scope. There were no prospective randomized clinical trials of course impact. Efficacy for most courses was with Kirkpatrick level 1 and 2 evidence of benefit by self-evaluations, and reporting small numbers of respondents. Few courses assessed skill retention with longitudinal data before and after training. Three courses, namely: Advanced Trauma Life Support (ATLS), Advanced Surgical Skills for Exposure in Trauma (ASSET) and Advanced Trauma Operative Management (ATOM) have Kirkpatrick's level 2-3 evidence for efficacy. Components of these 3 courses are included in several other courses, but many skills courses have little published evidence of training efficacy or skills retention durability. CONCLUSIONS: Large variations in course content, duration, didactics, operative models, resource requirements and cost suggest that standardization of content, duration, and development of metrics for open surgery skills would be beneficial, as would translation into improved trauma patient outcomes. Surgeons at all levels of training and experience should participate in these trauma skills courses, because these procedures are rarely performed in routine clinical practice. Faculty running courses without evidence of training benefit should be encouraged to study outcomes to show their course improves technical skills and subsequently patient outcomes. Obtaining Kirkpatrick's level 3 and 4 evidence for benefits of ASSET, ATOM, ATLS and for other existing courses should be a high priority.

Users Guide to Pitfalls and Lessons Learned About HBOC-201 During Clinical Trials, Expanded Access, and Clinical Use in 1,701 Patients.

Lessons learned during 1,701 clinical uses of HBOC-201, a polymerized bovine hemoglobin-based oxygen carrier (HBOC), were identified to provide management lessons and training material for future clinical trials and use. HBOC-201 contains 13 g/dL hemoglobin (Hb), is iso-oncotic, stable at 2°C to 30°C with shelf-life of 3 years, requires no cross-matching with half-life of 19 h, and plasma volume distribution. Adverse effects include increased blood pressure, oliguria, gastrointestinal (GI) symptoms, yellow skin and scleral discoloration, decreased pulse oximetry measurements, and transient increases in methemoglobin, hepatic, and pancreatic enzymes. There was no cardiotoxicity. Elevations in blood pressure were transient and were managed with vasodilators. Oliguria was of limited duration. GI symptoms were treated with smooth muscle relaxants. Yellow skin and sclera were self-limiting, caused by Hb metabolism. The most important clinical management errors were lack of understanding of volume expansion effects and the half-life properties of HBOC-201, and failure to repeat infusions. Early use of HBOC-201 for Expanded Access when Hb less than 5 g/dL optimized survival and minimized advanced resource utilization. For phase 3 trials, there was transfusion avoidance of 96% for 24 h, 70% for 1 week, with no difference in serious adverse events or mortality whether patients received at most 10 bags HBOC-201 or at most 3 units blood. More nonserious events occurred with HBOC-201. Age, history of cardiac disease, and Hb deficit, but not randomization to HBOC-201, were significantly predictive of cardiac ischemic events. Administration of HBOC-201 in1,701 humans showed it was well tolerated in a wide range of doses and clinical settings. HBOC-201 should be considered when blood is not available or an option.

Relative Efficacies of HBOC-201 and Polyheme to Increase Oxygen Transport Compared to Blood and Crystalloids.

BACKGROUND: Because total hemoglobin in circulation ([THb]) is an established predictor of clinical outcomes in anemic individuals, the relative efficacies of resuscitation fluids to increase [THb] can be used to design better hemoglobin-based oxygen carrier (HBOC) clinical trials. METHODS: Expected efficacies of HBOC-201 (13 g Hb/dL) and packed red blood cells (RBCs) (packed red blood cells [pRBCs], 24 g Hb/dL) to increase [THb] were calculated and interpreted in the context of severe adverse events (SAEs) in the HEM-0115 phase III clinical trial.The PolyHeme phase III clinical trial compared the HBOC, PolyHeme (10 g Hb/dL), with crystalloid control prehospital and packed RBCs in hospital. The comparative abilities of these resuscitation fluids to maintain [THb] were interpreted in the context of mortality. RESULTS: In HEM-0115, infusion of HBOC-201 increased [THb] by 0.18 ±â€Š0.03 g/dL (N=121) compared with 0.87 ±â€Š0.07 g/dL (n = 115) following one unit of pRBCs. These observed increases in [THb] were similar to expected increases for these fluids. Use of HBOC-201 was associated with 0.34 SAEs per patient compared with 0.25 SAEs per patient in the pRBC arm (P = 0.016).Hemoglobin Deficit was greater in HBOC-201-treated patients than in pRBC controls and emerged as a predictor of SAEs in a logistics model. Randomization to HBOC-201 had no power to predict SAEs.PolyHeme more effectively maintained [THb] than did crystalloid prior to arrival at hospital, associated with initially higher survival in the PolyHeme arm. Thereafter, PolyHeme subjects sustained lower [THb] and higher mortality than controls. CONCLUSION: Greater anemia in subjects randomized to HBOC-201 was consistent with the relative efficacies of HBOC-201 and pRBCs to increase [THb] and may have contributed to more SAEs in the HBOC arm of HEM-0115 and greater long-term mortality in the PolyHeme trial.

Blood Transfusion Indicators Following Trauma in the Non-Massively Bleeding Patient.

BACKGROUND: Establishing transfusion guidelines during trauma resuscitation is challenging. Our objective was to evaluate indications for transfusion in trauma patients who emergently received ≤2 units of red blood cells (RBC) during the first hour of resuscitation. METHODS: A single center retrospective study included non-massively bleeding trauma patients stratified into 2 groups: 1) with a clinical indication for transfusion and 2) with no indication for transfusion. Admission vital signs (VS), injury severity score (ISS), shock index, and laboratory values were compared between the two groups using the Wilcoxon rank-sum test. RESULTS: Among 111 non-massively bleeding trauma patients, 40 presented no indication for transfusion. All patients presented similar ISS and VS. The 71 patients presenting with an indication for transfusion had higher bicarbonate (22.6 vs 20.8) and lower lactate levels (4.7 v 6.6) (p<0.05). CONCLUSION: Lactate and bicarbonate blood levels may be potential indicators for RBC transfusion need during trauma resuscitation in non-massively bleeding patients.

Cadaver-Based Trauma Procedural Skills Training: Skills Retention 30 Months after Training among Practicing Surgeons in Comparison to Experts or More Recently Trained Residents.

BACKGROUND: Long-term retention of trauma procedural core-competency skills and need for re-training after a 1-day cadaver-based course remains unknown. We measured and compared technical skills for trauma core competencies at mean 14 months (38 residents), 30 months (35 practicing surgeons), and 46 months (10 experts) after training to determine if skill degradation occurs with time. Technical performance during extremity vascular exposures and lower-extremity fasciotomy in fresh cadavers measured by validated individual procedure score (IPS) was the primary outcome. STUDY DESIGN: We performed a prospective study between May 2013 and September 2016. RESULTS: Practicing surgeons had lower IPS and IPS component scores (p = 0.02 to 0.001) than residents (p < 0.05) and experts (p < 0.002) for vascular procedures. Frequencies of errors were no different among residents and experts. Practicing surgeons made more critical errors (p < 0.05) than experts or residents. Experts had shortest time to proximal vascular control. Fasciotomy procedural errors occurred in all participants. Cluster analysis of anatomy vs procedural steps identified tertiles of performance and wide variance (32.5% practicing surgeons, 26.5% residents vs 13% experts) for vascular procedures. Vascular control duration > 20 minutes (n = 21) and failure to decompress fasciotomy compartments were correlated with incorrect landmarks and skin incisions. Modeling found interval trauma skills experience, not time since training, was associated with lower IPS. CONCLUSIONS: Practicing surgeons with low trauma skills experience since training had lower IPS and component scores (p = 0.02 to 0.001) and more errors compared with experts and residents (p < 0.05). Surgeons, including experts with low interval experience performing trauma procedures, may benefit from refreshing of correct landmarks and skin incision placement identification.

Repeat lactate level predicts mortality better than rate of clearance.

BACKGROUND: Lactate clearance has been developed into a marker of resuscitation in trauma, but no study has compared the predictive power of the various clearance calculations. Our objective was to determine which method of calculating lactate clearance best predicted 24-hour and in-hospital mortality after injury. STUDY DESIGN: Retrospective chart review of patients admitted to a Level-1 trauma center directly from the scene of injury from 2010 to 2013 who survived >15min, had an elevated lactate at admission (≥3mmol/L), followed by another measurement within 24h of admission. Lactate clearance was calculated using five models: actual value of the repeat level, absolute clearance, relative clearance, absolute rate, and relative rate. Models were compared using the areas under the respective receiver operating curves (AUCs), with an endpoint of death at 24h and in-hospital mortality. RESULTS: 3910 patients had an elevated admission lactate concentration on admission (mean=5.6±3.0mmol/L) followed by a second measurement (2.7±1.8mmol/L). Repeat absolute measurement best predicted 24-hour (AUC=0.85, 95% CI: 0.84-0.86) and in-hospital death (AUC=0.77; 95% CI, 0.76-0.78). Relative clearance was the best model of lactate clearance (AUC=0.77, 95% CI: 0.75-0.78 and AUC=0.705, 95% CI: 0.69-72, respectively) (p<0.0001 for each). A sensitivity analysis using a range of initial lactate measures yielded similar results. CONCLUSIONS: The absolute value of the repeat lactate measurement had the greatest ability to predict mortality in injured patients undergoing resuscitation.

Head-camera video recordings of trauma core competency procedures can evaluate surgical resident's technical performance as well as colocated evaluators.

BACKGROUND: Unbiased evaluation of trauma core competency procedures is necessary to determine if residency and predeployment training courses are useful. We tested whether a previously validated individual procedure score (IPS) for individual procedure vascular exposure and fasciotomy (FAS) performance skills could discriminate training status by comparing IPS of evaluators colocated with surgeons to blind video evaluations. METHODS: Performance of axillary artery (AA), brachial artery (BA), and femoral artery (FA) vascular exposures and lower extremity FAS on fresh cadavers by 40 PGY-2 to PGY-6 residents was video-recorded from head-mounted cameras. Two colocated trained evaluators assessed IPS before and after training. One surgeon in each pretraining tertile of IPS for each procedure was randomly identified for blind video review. The same 12 surgeons were video-recorded repeating the procedures less than 4 weeks after training. Five evaluators independently reviewed all 96 randomly arranged deidentified videos. Inter-rater reliability/consistency, intraclass correlation coefficients were compared by colocated versus video review of IPS, and errors. Study methodology and bias were judged by Medical Education Research Study Quality Instrument and the Quality Assessment of Diagnostic Accuracy Studies criteria. RESULTS: There were no differences (p ≥ 0.5) in IPS for AA, FA, FAS, whether evaluators were colocated or reviewed video recordings. Evaluator consistency was 0.29 (BA) - 0.77 (FA). Video and colocated evaluators were in total agreement (p = 1.0) for error recognition. Intraclass correlation coefficient was 0.73 to 0.92, dependent on procedure. Correlations video versus colocated evaluations were 0.5 to 0.9. Except for BA, blinded video evaluators discriminated (p < 0.002) whether procedures were performed before training versus after training. Study methodology by Medical Education Research Study Quality Instrument criteria scored 15.5/19, Quality Assessment of Diagnostic Accuracy Studies 2 showed low bias risk. CONCLUSION: Video evaluations of AA, FA, and FAS procedures with IPS are unbiased, valid, and have potential for formative assessments of competency. LEVEL OF EVIDENCE: Prognostic study, level II.

Performance of Vascular Exposure and Fasciotomy Among Surgical Residents Before and After Training Compared With Experts.

Importance: Surgical patient outcomes are related to surgeon skills. Objective: To measure resident surgeon technical and nontechnical skills for trauma core competencies before and after training and up to 18 months later and to compare resident performance with the performance of expert traumatologists. Design, Setting, and Participants: This longitudinal study performed from May 1, 2013, through February 29, 2016, at Maryland State Anatomy Board cadaver laboratories included 40 surgical residents and 10 expert traumatologists. Interventions: Performance was measured during extremity vascular exposures and lower extremity fasciotomy in fresh cadavers before and after taking the Advanced Surgical Skills for Exposure in Trauma (ASSET) course. Main Outcomes and Measures: The primary outcome variable was individual procedure score (IPS), with secondary outcomes of IPSs on 5 components of technical and nontechnical skills, Global Rating Scale scores, errors, and time to complete the procedure. Two trained evaluators located in the same laboratory evaluated performance with a standardized script and mobile touch-screen data collection. Results: Thirty-eight (95%) of 40 surgical residents (mean [SD] age, 31 [2.9] years) who were evaluated before and within 4 weeks of ASSET training completed follow-up evaluations 12 to 18 months later (mean [SD], 14 [2.7] months). The experts (mean [SD] age, 52 [10.0] years) were significantly older and had a longer (mean [SD], 46 [16.3] months) interval since taking the ASSET course (both P < .001). Overall resident cohort performance improved with increased anatomy knowledge, correct procedural steps, and decreased errors from 60% to 19% after the ASSET course regardless of clinical year of training (P < .001). For 21 of 40 residents (52%), correct vascular procedural steps plotted against anatomy knowledge (the 2 IPS components most improved with training) indicates the resident's performance was within 1 nearest-neighbor classifier of experts after ASSET training. Five residents had no improvement with training. The Trauma Readiness Index for experts (mean [SD], 74 [4]) was significantly different compared with the trained residents (mean [SD], 48 [7] before training vs 63 [7] after training [P = .004] and vs 64 [6] 14 months later [P = .002]). Critical errors that might lead to patient death were identified by pretraining IPS decile of less than 0.5. At follow-up, frequency of resident critical errors was no different from experts. The IPSs ranged from 31.6% to 76.9% among residents for core trauma competency procedures. Modeling revealed that interval experience, rather than time since training, affected skill retention up to 18 months later. Only 4 experts and 16 residents (40%) adequately decompressed and confirmed entry into all 4 lower extremity compartments. Conclusions and Relevance: This study found that ASSET training improved resident procedural skills for up to 18 months. Performance was highly variable. Interval experience after training affected performance. Pretraining skill identified competency of residents vs experts. Extremity vascular and fasciotomy performance evaluations suggest the need for specific anatomical training interventions in residents with IPS deciles less than 0.5.

Can hyper-realistic physical models of peripheral vessel exposure and fasciotomy replace cadavers for performance assessment?

BACKGROUND: Work-hour restrictions have reduced operative experience for residents. The Advanced Surgical Skills for Exposure in Trauma (ASSET) course fills this training gap. Cadaver use has limitations including cost and availability. Hyper-realistic synthetic models may provide an alternative to cadavers. We compared same surgeon performance between synthetic and cadaveric models to determine interchangeability for formative evaluation. METHODS: Forty residents (<4 weeks after ASSET) and 35 faculty (mean, 2.5 ± 1.3 years after ASSET) exposed axillary, brachial, and femoral arteries, and performed lower extremity fasciotomy. Separate evaluators and random starting order between models were used for participants. Individual procedure scores and aggregate procedure scores, a trauma readiness index, evaluated participants. Student's t and χ tests were used where appropriate. p Values less than 0.05 were considered significant. RESULTS: For same surgeons, faculty, but not residents, had higher trauma readiness index on the synthetic model (0.63 vs. 0.70, p < 0.01; 0.63 vs. 0.67, p = 0.06, respectively). Scores were not significantly different between models for residents except for the brachial artery exposure (0.68 vs. 0.75, p < 0.01), which was the least realistic of all procedures. Faculty did significantly better on the synthetic model in all procedures. All participants completed procedures nearly twice as quickly (5.61 ± 3.21 vs. 10.08 ± 4.66 minutes) and performed fewer errors on the synthetic model (113 vs. 53, p < 0.01; 118 vs. 76, p = 0.03, respectively). CONCLUSION: Same surgeons performed procedures quicker and with fewer errors on the synthetic model. Residents performed similarly on both model types, this likely represents the unfamiliarity neophytes bring to new procedures. This suggests that the synthetic model, with easily discernible and standardized anatomy, may be useful in the early stages of training to understand critical procedural steps. The difficulty of the cadaver is more apt to assess and evaluate the experienced surgeon and identify opportunities for improvement. LEVEL OF EVIDENCE: Prognostic, level III.

Reliable Collection of Real-Time Patient Physiologic Data from less Reliable Networks: a "Monitor of Monitors" System (MoMs).

Research and practice based on automated electronic patient monitoring and data collection systems is significantly limited by system down time. We asked whether a triple-redundant Monitor of Monitors System (MoMs) to collect and summarize key information from system-wide data sources could achieve high fault tolerance, early diagnosis of system failure, and improve data collection rates. In our Level I trauma center, patient vital signs(VS) monitors were networked to collect real time patient physiologic data streams from 94 bed units in our various resuscitation, operating, and critical care units. To minimize the impact of server collection failure, three BedMaster® VS servers were used in parallel to collect data from all bed units. To locate and diagnose system failures, we summarized critical information from high throughput datastreams in real-time in a dashboard viewer and compared the before and post MoMs phases to evaluate data collection performance as availability time, active collection rates, and gap duration, occurrence, and categories. Single-server collection rates in the 3-month period before MoMs deployment ranged from 27.8 % to 40.5 % with combined 79.1 % collection rate. Reasons for gaps included collection server failure, software instability, individual bed setting inconsistency, and monitor servicing. In the 6-month post MoMs deployment period, average collection rates were 99.9 %. A triple redundant patient data collection system with real-time diagnostic information summarization and representation improved the reliability of massive clinical data collection to nearly 100 % in a Level I trauma center. Such data collection framework may also increase the automation level of hospital-wise information aggregation for optimal allocation of health care resources.

Automated continuous vital signs predict use of uncrossed matched blood and massive transfusion following trauma.

BACKGROUND: Recognizing the use of uncross-matched packed red blood cells (UnXRBCs) or predicting the need for massive transfusion (MT) in injured patients with hemorrhagic shock can be challenging.A validated predictive model could accelerate decision making regarding transfusion. METHODS: Three transfusion outcomes were evaluated in adult trauma patients admitted to a Level I trauma center during a 4-year period (2009-2012): use of UnXRBC, use of greater than 4 U of packed red blood cells within 4 hours (MT1), and use of equal to or greater than 10 U of packed red blood cells within 24 hours (MT2). Vital sign (VS) features including heart rate, systolic blood pressure, and shock index (heart rate / systolic blood pressure) were calculated for 5, 10, and 15 minutes after admission. Five models were then constructed. Model 1 used preadmission VS, Model 2 used admission VS, and Models 3, 4, and 5 used continuous VS features after admission over 5, 10, and 15 minutes, respectively, to predict the use of UnXRBC, MT1, and MT2. Models were evaluated for their predictive performance via area under the receiver operating characteristic (ROC) curve, positive predictive value, and negative predictive value. RESULTS: Ten thousand six hundred thirty-six patients with more than 5 million continuous VS data points during the first 15 minutes after admission were analyzed. Model using preadmission and admission VS had similar ability to predict UnXRBC, MT1, or MT2. Compared with these two models, predictive ability was significantly improved as duration of VS monitoring increased. Continuous VS for 5 minutes had ROCs of 0.83 (confidence interval [CI], 0.83-0.84), 0.85 (CI, 0.84-0.86), and 0.86 (CI, 0.85-0.88) to predict UnXRBC, MT1, and MT2, respectively. Similarly, continuous VS for 10 minutes had a ROCs of 0.86 (CI, 0.85--0.86), 0.87 (CI, 0.86-0.88), and 0.88 (CI, 0.87-0.90) to predict UnXRBC, MT1, and MT2, respectively. Continuous VS for 15 minutes achieved the highest ROCs of 0.87 (CI, 0.87-0.88), 0.89 (CI, 0.88-0.90), and 0.91 (CI, 0.91-0.92) to predict UnXRBC, MT1, and MT2, respectively. CONCLUSION: Models using continuous VS collected after admission improve prediction for the use of UnXRBC or MT in patients with hemorrhagic shock. Decision models derived from automated continuous VS in comparison with single prehospital and admission VS identify the use of emergency blood use and can direct earlier blood product administration, potentially saving lives. LEVEL OF EVIDENCE: Therapeutic study, level III.